Growth and physical properties of melt textured (Gd,Y)Ba2Cu3Ox

Melt textured samples grown from mixtures of GdBa2Cu3Ox with Y2BaCuOx, and from GdBa2Cu3Ox with Gd2BaCuOx, were successfully grown in air using the top seeding method employing NdBa2Cu3Ox seed crystals. For GdBa2Cu3Ox/Y2BaCuOx, the superconducting transition temperature is 91 K (diamagnetic onset) and the critical current at 77 K is 25 000 A/cm(2) at zero applied field and above 10 000 A/cm(2) at 2 T. The irreversibility field at 77 K is about 6 T. The green phase particles are small and well dispersed, even without the addition of Pt. However, samples grown in air from the GdBa(2)Cu(3)Ox/Gd2BaCuOx mix had T-c's of 75-80 K, fairly low critical currents and showed large green phase inclusions. (C) 1998 Published by Elsevier Science B.V. All rights reserved.